In 1943 a DeHavilland Mosquito in BOAC markings landed at RAF Leuchars in Scotland carrying a valuable passenger- Danish physicist Niels Bohr, the 1922 winner of the Nobel Prize in physics. In a conference in Washington DC in 1939, Bohr detailed how the uranium isotope U-235 could be used to create a chain reaction in an atomic bomb. By 1943 the Nazis were rounding up and deporting the Jews in Denmark and as his mother was Jewish, Bohr was at risk. Word got out that he was about to be arrested and given the choice between joining Hitler's atomic weapons project or be sent with his family to a concentration camp.
With the help of the British secret service, Bohr was smuggled to Sweden and then flown in an improvised bunk in the bomb bay of the Mosquito from Stockholm to Scotland. From there he was flown onward to England and then the United States to join the Manhattan Project.
The Mosquito flew approximately 200 flights in BOAC colors between Stockholm and the UK during the war conveying clandestine personnel and war materiel. Only the Mosquito was fast enough to evade patrolling German fighters over the North Sea.
Source: Aviation History, September 2009. "The Magnificent Merlin" by Nicholas O'Dell, p32.